The invention relates to a continuous, and in particular, double-belt, press as well as to a method for controlling the course of the pressing belt. The double-belt press comprises two revolving belts that are urged against each other. DE 41 10 678 C1 as well as DE 198 24 723 C1 disclose presses of the type according to the invention.
The continuous press is used to compress wood particles, fibers, chips provided with adhesives or an already pre-compressed fiber mat, in particular while heat is supplied.
There is the problem, particularly in a double-belt press, that a revolving belt runs out to the left or the right seen in the direction of transport. The problem of the belt running out is especially problematic in the pressing area. In a double-belt press, this area is located between the two rollers at the front and rear end around which the respective steel-belt is guided.
In the pressing area, there are rotating rods or rollers that suitably exert pressure on the respective pressing belt in the direction of the material to be compressed. In particular, several rotating rods are arranged parallel to each other and are attached to a chain, on the right hand side and the left hand side. The two chains are driven by means of gearwheels. The gearwheels are mounted laterally on an input shaft and an output shaft, respectively. In this manner, the rotating rods, together with the chains, also form a revolving belt. Therefore, the rotating rods or the belt formed by them on one side abut a pressing belt.
The above mentioned features belong to the present invention individually or in combination.
DE 41 10 678 C1 discloses a feed-through press comprising steel belts that are driven in a revolving manner. In the pressing area, the respective steel belt is guided as such by means of rotating bodies or rotating rods. The course of the respective steel belt is corrected by varying the pressure the rotating rods exert on the pressing belt.
The course of a steel belt employed as a press belt may in principle be controlled successfully through the change in the pressure that the rotating rods exert on the pressing belt. In the aforementioned solution of the problem, the pressure acting on the material to be compressed is disadvantageously also varied. This results in negative effects on the quality of the product.
This present problem occurs especially in particularly long presses. Here, a revolving pressing belt tends especially strongly to deviate from the desired course in the pressing area.
A method for adjusting the infeed contour of the infeed mouth of a continuous press can be gathered from DE 198 247 23 C1. According to this, the upper infeed plate of the infeed mouth is deformed by means of differential cylinders while forming an infeed contour with at least a mat contact zone on the side of the infeed, a mat clamping zone adjacent to the mat contact zone and a mat joining zone adjacent to the mat clamping zone. In this manner, both material jam occurring during the compaction of the material as well as blowing out, even at high press speeds, are avoided.